Magnetic drive for textile machines



My 2, 1.950 A. PETERSEN- A2,506,315

MAGNETIC DRIVE FOR TEXTILE MACHINES Filed Oct. 10.- 1947 2 Sheets-Sheet 1 ff yf Patented May 2, 1950 MAGNETIC DRIVE FOR TEXTILE MACHINES Anker Petersen, South Boston, Mass., assignor to Petersen Braiding Machine Company, a copart- Application October 10, 1947, Serial No. 779,186

8 Claims.

This invention pertains to drive means for imparting movement to a bobbin carrier and is useful, for example, in weaving looms, braiding ma chines or in fact in any machine wherein a thread-carrying bobbin or shuttle must `be moved along a predetermined path. As here illustrated, by way of example but without limitation as to its use, it is shown as embodied in a braiding machine of the general type wherein one set of bobbin carriers (hereinafter for convenience referredA to as the inner set) is revolved in an annular path about the axis of the machine, while a second set of bobbins or bobbin carriers (hereinafter referred to for convenience as the outer set), disposed in a circle concentric with the axis of the machine, either revolves in a direction opposite to the carriers of the inner set or remains stationary. The strands from the bobbins of the outer set are so controlled that'each carrier of the inner set passes alternately over and under strands from the outer set. A machine of this general type is shown in the patent to Anker Petersen, No. 1,796,938, granted March 17, 1931, for example. In the patented construction the carriers of the inner set are moved along their circular path by means of drive rolls which are bodily revolved in a path concentric with that in which the carriers move, the peripheries of these drive rolls engaging the peripheries of complemental driven rolls mounted on the carriers. With this arrangement the strands of the carriers or bobbins of the outer set pass between the contacting peripheries of the .driving and driven rolls without substantialv difficulty, thus lessening the danger of injury to the strands as compared with the results of the use of other and prior types of drive. However, for the most effective. operation of such roll drive, it is necessary to rotate the drive rolls on their own axes as they revolve in their operative path; the provision of means for thus rotating these drive rolls adds to the cost of machine manufacture and upkeep, and wear of the parts after long use may result in lost motion with consequent lag at starting and over-run in stopping. The patent to Earl Petersen, No. 2,177,742, dated October 31, 1939, discloses an arrangement wherein a. magnetic drive is substituted for the mechanical roll-drive of the aforesaid Anker Peterson patent, and the use of this magnetic drive completely eliminates allpossibility of abrasion of the strands from the outer set of carriers due t the action of the driving means; it reduces the cost of machine manufacture and maintenance and also reduces noise and vibration.

'I'he present invention constitutes an improvement upon the magnetic drive of the Earl Petersen patent. The principal object of the present invention is to provide a magnetic drive for braiding machine carriers or the like which will be powerful enough to drive the braiding carrier at a very high speed, even though the carrier be of a size to support a bobbin of large capacity and which is also effective to start the carrier into operation without appreciable lag when the ma.-A chine starts, and to stop the carrier without overtravel when the machine is stopped. A further dbject is to provide a magnetic drive for a carrier of a braiding machine or the like which affords a magnetic field of substantial area, for example, a eld which extends over substantially the entire circumferential width of the carrier but which is created by means which does not interfere with the bobbin or restrict the permissible size of the latter, and without necessitating any undesirable location of the bobbin upon the carrier. A further object is to provide a magnetic drive for a braiding machine carrier or the like so devised that ample magnetic driving force for each carrier is attained by the use of 'a single magnet in cooperation with a soft iron armature or armatures mounted on the carrier. Other and further objects and advantages of the invention will be pointed out in the following more detailed description and by reference to the accompanying drawings wherein Fig. 1 is a vertical diametrical section, partly broken away and with parts omitted, showing the head of a braiding machine embodying the present invention;

Fig. 2 is a fragmentary plan View, with parts omitted, of the machine shown in Fig. 1;

Fig. 3 is a fragmentary side elevation, to larger scale, of the upper part of the machine shown in Fig. 1 'and with many parts omitted and parts in section, showing one of the braiding carriers and the means for driving it; v

Fig. 4 is a plan view of the supporting ring on which the driving magnets are mounted;

Fig. 5 is a bottom View, partly broken away, oi' one of the carriers for a bobbin of the inner series;

' Fig. 6 is a fragmentary perspective view, to larger scale than Fig. 5, partly in vertical section, showing the bottom plate of the carrier and the armature bars mounted therein; and

Fig. 7 is a perspective view, to larger scale. illustrating a desirable form of drive magnet.

Referring to the drawings, the frame of the machine is shown as comprising a spider having arms 23 which radiate from the base (not shown) of the machine, these arms supporting the annulus 22 having a seat for the cam ring 23 provided with the cam groove 24 on its inner face. 'I'he base of the machine also carries the iixed hollow shaft 25 which supports the braiding die D having a central aperture defining the braiding point. A sleeve 23 turns on the shaft 25, the lower end of the sleeve 23 preferably resting upon an l-anti-friction step bearing (not'shown) carried by the base. Any suitable type of anti-friction bearing 21* is interposed between the hollow sh-aft 25 and the sleeve 23 near the upper end of the latter. The hub 23 of a spider device is splined to the sleeve 2l and this spider device carries an annular gear 29 which meshes with a pinion 30 on a drive shaft 3|. The hub 23 supports the inner race 32 of a ball bearing while the outer race 33 of this bearing supports -a ring member 34 to which an annular gear 35 is secured. This gear 35 meshes with the pinion 33 which thus drives the gears 29 and 35 in opposite directions.

The ring 34 supports a plurality of spaced arms 33 which carry an annulus 31 concentric with and spaced inwardly from the cam ring 23. A second ring member 33 is secured to the upper edge of the ring 31 or it may be integral therewith if desired, and this member 33 carries inwardly projecting arms 39 connected by a circumferentially extending ring 40. Downwardly directed arms 4| extend from the ring 40 and at their lower ends support a guide ring 42, concentric with the ring 31. The opposed faces of rings 31 and 42 are provided with grooves 43 and 44, respectively. constituting guideways for the inner series of bobbin carriers hereinafter more fully described. Each of the grooves 43 and 44 h-as spaced upper and lower 4walls which are normally circumferentially continuous so that when a carrier has once been engaged with these grooves it is held positively in position and, while free to move circumferentially, is constrained against substantial axial movement. As some suitable point, either in the ring 31 or the ring 42, a removable section (not shown) is provided to permit insertion and removal of the carriers when desired.

A hub member 45 is secured to the upper part of the sleeve 25 and carries a plate 45 which supports a ring 41 which constitutes a support or carrier for the drive m-agnets 49. There are as many of these drive magnets as there are carriers of the inner series. Four such magnets are here illustrated (Fig. 4). These magnets (Fig. 7) are preferably of U or horseshoe shape, each having the south and north poles S and N, respectively. These magnets are permanent m-agnets of the high flux-density type now available, such magnets having a magnetic life of long duration.

These magnets 43 are of substantial length for example three inches or more, and each is arranged with its long dimension substantially perpendicular to a radius of the supporting ring 41. Preferably the upper surfaces of the poles of these magnets are flush with the upper surface of the ring 41, although they may project upwardly beyond said surface if desired. These magnets are secured in openings in the ring 41 in any desired way, for example, by a press fit. The rings 41 are of a non-magnetic material, for example aluminum. Preferably, the length of each mag- .net approximates the circumferential -width of one of the carriers of the inner series, and is desirably at least as long as the bobbin or spool -which is mounted on the carrier. Preferably, the pole pieces of these magnets are shaped to provide a series of spaced ribs 43. As here illustrated, each pole piece has six of these ribs, corresponding ribs of the two pole pieces being aligned withr each other. These ribs produce zones of intense magnetic flux.

The ring 49 forms a convenient support for a series of brackets 53 (in numbercorresponding to the number of bobbin carriers of the inner series) which are attached to the ring in any suitable manner and spaced at regular intervals circumferentially of the ring. 'I'hese brackets support the bobbins 54 of one series which, for convenience, is here referred to as the outer series, the brackets 53 being referred to as the bobbin carriers of the outer series. 'I'hese brackets 53 are of sumcient height to accommodate rotating bobbins 54 of the desired diameter.

A warp lever is associated with each of the brackets 53. A bracket 3i (Figs. 1 and 2) is secured to the outer surface of the ring 31 at a point corresponding to the location of each bracket 53, each bracket 3| comprising a spacer member 32 having a recess 53 at its inner side for the reception of a part of the warp lever. The member 32 is provided with a pivot pin 65 about which the warp lever swings. The warp lever shown comprises a substantially rigid base portion consisting of two elongate strips 66 and 61 (Fig. 2) of sheet metal spaced apart at one end to straddle over the spacer member 62 and having aligned journal openings for the pivot pin 65, one of these members 6i having its pivoted end disposed in the recess 63 and the other engaging the other surface of the part 62. The

35 ends of these parts 56 and 61 may, if desired. be welded to the pivot pin l5. The members 56 and 61 converge and are united at their other ends by means of a pin 63 which constitutes a pivot for an anti-friction cam follower 59 which engages the cam slot 24 in the annulus 23. The warp lever is extended beyond the pin 59, as shown at 12 (Fig. 2), and the free portion of the lever is curved substantially concentrically with the cam ring 23 and at its end is furnished with a thread guide aperture or eye which is disposed radially opposite to a vertical slot 14 (Fig. l) in the ring 31. The yarn Y from the bobbin 54 passes down through an elongate guide eye in a bracket secured to the ring member 33 and thence through the hook end 16 of a detector and thence down through a guide coaxial with the pivot pin 55 and thence lengthwise of the warp lever and through the guide eye at the end of the latter, and thence inwardly beneath the 55 ring 42 to the braiding point defined by the die D. The'bobbins 8| of the inner series are journaled in suitable bearings in bobbin carriers 32 (Figs.

2, 3 and 5). Each of these bobbin carriers 3| comprises a rigid frame made as light as possible, consistent with strength and rigidity, for example, from aluminum or magnesium or some alloy of these metals. Each bobbin carrier is provided with supporting elements, here shown as anti-friction rolls 33 and l34 at itsl outer edge,

which engage the guideway 43 in the ring 31.

At its inner edge each carrier is provided with a supporting element, here shown as a roller 35,

which engages the guideway 44. Preferably, the rolls 33, 34 and 35 have anti-friction bearings.

Each of the carriers 32 is provided with a bottom plate 33 (Figs. 5 and 6) which may be integral with the carrier frame or which, as here illustrated, is an independent part secured to the underside of the frame by screws, bolts, weld- 75 ing or brazing. This bottom plate 33 is arranged below the horizontal plane which is tangent to the maximum diameter of the bobbin 8|, so that the plate does not in any way interfere with the free rotation of the bobbin. As illustrated, this plate 98 is elongate in the direction of travel of the carrier, extending across the entire width oi the carrier and is at least as long as the maximum length of one of the magnets 48. The plate 99 supports a series of spaced, parallel armature bars 9| of soft iron. These bars are preferably set into the substance of the` plate 90 so as to be flush with the' lower surface of .the

'latten As shown in Fig. 6, these bars 9| are provided on their opposite edgeswith grooves 93 and are thus interlocked with the material of the plate 99. The plate 90 may be a casting of aluminum, magnesium or other non-magnetic material, and the bars 9| may-be cast into the substance of the supporting plate. However, it is contemplated that the bars 9| may be secured in other desired manner to thel plate 90. For example, the latter may be of sheet material, and the bars 9| may be attached to it by ilanges of the sheet material or by rivets orthe like. The armature bars 9| are spaced apart equal distances and by the same amount as the ribs 49 of the pole pieces of the magnets 49 so that one of the bars 9| is normally registered with each of the ribs 49. The bars 9| are of a length (radially of the path of the carrier) sub-y stantially equalling the transverse thickness of thefmagnet, each of the armature bars 9| being disposed directly above and v eryclose to one of the ribs of the magnet. While single magnets 49 are here illustrated, and while each carrier l2 is shown as provided with a single row of armature bars,1t is obvious that if additional driving force be desired, as, for example, when the yarn masses on the carriers are very large, two or more of the magnets 49 may be arranged as a group, the several magnets of a group being at diil'erent distances from the center of the machine, and corresponding rows of armature bars being similarly arranged.

. With this arrangement, there is no mechanical driving connection between the rotating ring 41 and the carriers 82, but by reason of the intense magnetic ux in the vicinity of the ribs 49 of the magnets, the size of the magnets and the carriers. This form of drive permits the yarn Y from the bobbins of the outer series to pass freely under the carriers 82 without contact with any mechanical part which would subject them to abrasion, substantial compression or retarding force, and thus by the use of this drive, yarn breakage, as compared with that which occurs in machines of the customary type. is very greatly reduced and in fact substantially eliminated. With this drive it is possible to braid yarns which are very tender and fragile and to drive the machine at very great speeds without substantial Vdanger of breakage of yarn.

By the use of the single elongate magnets 48 and armature bars herein disclosed it is possible to obtain suillcient magnetic driving force, thus avoiding the necessity of mounting magnets on the carriers. The series of narrow armature bars 6 9| weighs substantially less than a magnet, and thus the weight or the carrier is very substantially reduced as compared with an arrangement in which opposed magnets are mounted on the carrier and driving ring, respectively. Moreover. the armature bars 9| may be so narrow, vertically, as to occupy but little space, and thus the row may be extended across the entire width of the carrier without interfering ywith the free rotation ofthe bobbin or imposing any limits upon the diameter of the bobbin.- As above suggested. more than one series of amature bars may be used'on the same carrier, the several series, for example, extending across the entire width of the carrier in a radial direction. It is thus possible to increase the magnetic driving force very substantially as compared with `previous constructions in which magnets are mounted on the carrier itself, but without reducing the size of the bobbin or unduly increasing the weight of the carrier.

While a desirable embodiment of theL invention has here been described by way oi example, it is to be understood that the invention is broadly inclusive of any modiilcations falling within the scope of the appended claims.

I claim:

1. vIn a textile machine, in combination, a

bobbin carrier, means for guiding it to move in a predetermined path, a permanent magnet of unitary construction having a pole piece which is elongate in the direction of travel of said carrier, said pole piece being divided lengthwise into a plurality of spaced pairs of poles aording y a distance substantially equalling the effective Vlength of said magnet pole piece.

41, and in stopping there is no over-travel ofthe l2. In a textile machine, in combination, a bobbin carrier, means for guiding it to move in a predetermined path, a permanent magnet of unitary construction having a pole piece which is elongate in the direction of travel of the carrier, said pole piece being divided into a series oi' parallel spaced ribs providing a magnetic field having spaced zones of high magnetic flux, and a series of parallel armatures, in number equalling the number of magnet pole ribs, said armatures being ilxed to the carrier and being spaced apart so that each armature cooperates with one of the ribs of the magnet pole piece.

3,. In a circular loom textile machine, in combination, a bobbin carrier, means for guiding it to move in\ a predetermined path, a plurality of permanent U-shaped magnets of unitary construction having pole pieces which are elongate in the direction of travel of the carrier, each pole piece being divided into a series of parallel ribs thereby to provide spaced pairs of poles aiording a magnetic eld having spaced zones of high magnetic ux, and a series of narrow, parallel armatures ilxed to the carrier, each armature being of a length to extend across both poles of the magnet, the armatures being so spaced apart that each lies in one of said zones of high magnetic flux.

4.- In a braiding machine of the class described comprising an outer rotary member and an inner rotary member, means for turning said outer and 'lo inner members in opposite directions, radially spaced concentric guides carried .by the outer rotary member, said guides having grooves dening annular paths i'or the outer and inner ends, respectively, of a bobbin carrier, a bob- 1 bin carrier having its ends disposed in the respective grooves, and means for driving the bobbin carrier, said driving means comprising a permanent magnet mounted on the inner rotary member, and a series of spaced amature bars xed to the carrier and extending in a substantially radial direction, the permanent magnet having a pole piece which, in the direction of the carrier path, is substantially as wide as the carrier, said pole piece having a series of parallel ribs; in number equalling thenumber of armature bars, and so spaced that each rib registers with one of said bars.

5. In a braiding machine of the class described comprising an outer rotary member` and an inner rotary member, means for turning said outer and inner members in opposite directions, radially spaced concentric guides carried by the outer rotary' member, said guides having grooves dening annular paths for the outer and inner ends, respectively, of a bobbin carrier, a bobbin carrier having its ends disposed in the respective grooves, and means for driving the bobbin carrier, said driving means comprising a permanent magnet mounted on the inner rotary member, and a series of substantially parallel spaced armature bars, the carrier comprising a bottom plate in which said bars are embedded, the permanent magnet being of U-shape with its poles radially spaced, each pole being of a iength,vin the direction of rotation of the carrier, substantially equalling 'the circumferential width of the carrier, the outermost of the armature bars being spaced from each other a distance substantially equalling the circumferential length of the magnet pole pieces.

6. In a braiding machine of the class described comprising an outer rotary member and .an inner rotary member, means for turning said outer and inner members in opposite directions, radially spaced concentric guides carried by the outer rotary member, said guides having grooves denning annular paths for 4the outer and inner ends, respectively, of a bobbin carrier, a bobbin carrier having its ends disposed in the respective grooves, and means for driving the bobbin carrier, said driving means comprising a permanent magnet mounted on the inner rotary member, and a series of spaced armature bars, the carrier comprising a bottom plate which underlies the bobbin and in which said bars are embedded, the permanent magnet having a pole piece which, in the direction of rotation of the carrier, substantially equals in length the circumferential width of the carrier, the pole piece having a series of spaced ribs in number equal to the number of armature bars, said ribs dening spaced zones of intense magnetic flux, each of the armature bars being located within one of said zones. l

7. A braiding machine of the kind having a rotating annular member and a series of bobbin carriers mounted thereon, a second series of bobbin carriers, means guiding the carriers of the latter series to move'in a path concentric with:

said annular member, and magnetic means for,

moving the carriers of said second series along= said path, said magnetic means comprising a se-A ries of vertically narrow, substantially parallel: armature bars fixed to the lower part of each carrier, each series extending substantially from one radial edge of its carrier to the other, a permanent magnet cooperating with each series of; armature bars, and means for moving the several magnets in a path concentric with said annular'` member, each magnet having a pole piece which,` in the direction `of travel of the carriers, substantially equals in length the circumferential. width of the series of armature bars.

8. A braiding machine of the kind having a braiding die defining the braiding point, an an-r nular rotary member concentric with the die; means for turning said member, a series of bobbin carriers mounted on the annular member,l a pair of concentric guides fixed relatively to said annular member, said guides having opposedA grooves, a second series of bobbin carriers, said latter carriers having parts engaging said grooves and being supported and guided solely by the latter, the innermost of said concentric guides being wholly to one side of the yarns leading from the carriers of the second series to the. braiding point, means for guiding the yarns fromeach carrier of the first-named series alternately,l over and under successive carriers of the secondv series, and magnetic means for moving the car--A riers of the second series along their guides in ay direction opposite to the movement of said ari-` nular member, said magnetic means comprising a series of spaced armature bars xed to each cari rier and disposed in a plane substantially perpendicular to the axis of the annular member. and below the bobbins on the carriers, said series of armature bars extending substantially fromone radial edge oi' the carrier to the other, a per--v manent magnet cooperating with each of said series of armature bars, and a rotating support for the magnet, each magnet having a pole piece which, in the direction of rotation of the carriers, is substantially equal to the width of the corresponding carrier, the pole piece of each magnet having a series of projecting ribs in number equal to the number of armature bars of the corresponding series, said ribs being so spaced from the plane of the armature Abars that the latter lie within zones of intense magnetic flux emanating from said ribs.

A` NKER PETERSEN.

REFERENCES CITED The following references are ille of this patent:

UNITED STATES PATENTS of record in the 

